Device for supplying gaseous mixtures to internal combustion engines



June 20; 1944. .LPOINSIGNON DEVICE FOR SUPPLYING GASEOUS MIXTURES TO INTERNAL COMBUSTION ENGINES Filed March 14, 1942 M NN Patented June 20, 1944 2,352,003 DEVICE FOR SUPPLYING olisnons MIX- TUBES ENGINES 'TO COMBUSTION Jean Poinsignon, Olermont-Ferrand, France; vested in the Alien Property. Custodian Application March 14, 1942,- Serial No. 434,667

In France ctobcr16, 194i) a U 6 Claims. .(Cl.-48 184) I The present'invention relates to the feeding of internal combustion engines by meansof gaseous fuels and has for its primary object to provide a device of improved and simplified construction for feeding this type of engines with a constant compositionmixture of combustible gas such as lighting gas or producer gas (hereafter called gas) and of combustion-promoting gaseous fluid such as atmospheric air (hereafter called air) so as to keep the kinetic efllciency of the engine as steady as possible.

Another object of theinvention is to provide a gaseous mixture feeder wherein the inflow of the two constituents of the mixture is so automatically adjusted that the richness of said mixture remains substantially constant and the volume of gaseous mixure fed to the engine copes at all times with its rate of operation and consumption. Still another objectof the invention is to providefor feeding a gaseous fuel mixture to an internal combustion engine a device comprising mixture-intermingling means associated with self-regulating means whereby any pressure decrease in the gaseous fuel inflow, for example due to clogging of the scrubber interposed between the gas producer and the device, is automatically compensated so as to maintain the ratio of the mixture constituents substantially constant. I A further object of the invention is to provide a gaseous fuel mixture feeder for an internal combustion engine, the operation of which is so automatically adjustable as to ensure constancy of mixture regardless of the position of the throttle valve controlling the outflow of said mixture to the engine induction manifold.

With these and such other objects in view as will incidentally appear "hereafter, the invention comprises the novel construction and combination of parts that will now be described in detail with reference to the accompanying drawing which exemplify several embodiments of the inof a pair of, spaced nembranes. p I

.Figure 4 is a diagrammatic view drawn "on a sma er sca e oi a o structional form" similar throughout the several views. I

to the one shown in Fig. 1 but comprising no mixing chamber for the gas and air."

Like reference characters designate like parts 7 As illustrated in Figs. 1 to 3 inclusive, the device may comprise a pairof nozzles ill; I i having Venturi outlines and projecting in converging relation through the oppositely slanting top sides of'a mixing chamber I2 connected to an outlet pipe l3 fitted with a throttle valve M of conventional structure and operation and connected in turn with the engine induction manifold (not shown); I

The nozzle I0 is provided at the end of a pri imary inlet pipe l5through whicha gaseous fuel such for example as lighting gas or producer gas may be admitted' as shown by the arrow" a A secondary inlet'pipe serves for the intake of theair which flows as shown by the arrow 6L "The'pipe I6 extends downwardly into a tightly closed casing'or enclosure ll andis elbowed at its lower end as shown at I8. The lower mouth l8 of the air intake pipe Hi is controlled by a diskshaped valve l9 which is urged by'a compression spring into closingf'positio'n. The spring 20 is coiled under suitable compression between the valve I9 and the adjacent end face of an adjuster screw 21 engaged in a tapped nipple 22 on the casing "and having an extension-23 by which it can be conveniently operated, manually for varying-the pressure exerted by the spring on the valve.

In the constructional form 'showniii Fi l, the inside, of the casing I1 is divided intoa 'pairof compartments sealed from each other by 'a resilient vdepressibl membrane 24 having its peripheral edge tightly clamped'between contiguous fianges 25, 26 formed on the outer wall of the casing ll. The .central region of the membrane 24 which may be suitably reinforced or fitted with a small stiff member to that effect has a rigid connection 21 in the form of a push rod with the disk valve "I9. "The left hand side or sec- ;ondary compartment 28 defined bythe membrane and the inner wall of the casing ll is connected with'the nozzle II by meansof a tube 29. The

right hand side or primary compartment 30 also defined by the membrane 24 and the inner wall of the casing I! communicates by means of a pressure-tapping tube 3| of small sectional area withthe gas intake or primary pipe l5.

Briefly described, the operation of the device shown in Fig. 1 is as follows: At rest, the membrane 24 and the "disk valve 19 occupy the positions shown in dotted lines. Therefore, the air zle l0.

suming of course the throttle fvalve Hi to befopen, th gaseous mixture flows'as shown" by cannot flow into the mixing chamber l2. However, when the engine (not shown) is started, there occurs a depression which propagates itself through the induction manifold and up through the mixing chamber 12. This depression draws the gas through the intake pipe 15 and by 'creatingja partial vacuum in=-thefsecond+ ary compartment 28 of -the enclosure 'l 'l 'unseats the valve 19 against the antagonistic resistance exerted by the spring 20, so that the air canflow along the path shown-by, thearrows 41 ,11

and a into the chamber I l ier L mixed with the gas fed intoit'thr'ough From the mixing chamber 12, and asit becomes the nozthe arrow a through the induction. pipe l3 towards the engine (not shown).

derstood, the casin I I divided by the fiexible zles ll], II to have, so;far,as;. the. flow of the two fluids is concerned, the same characteristics (which may be readily reckoned in a mathematical way in accordance with known laws of thermodynamics) it willibe seenthat insofar as the equality of pressure is preserved at the inlet of the nozzles. l0,.,l l, the ratio of the quantities of gas and, air which enter ,the mixing chamber |2y-is maintained constant regardless of their original rates :of feed .through, the pipes andlfi. 'By'varying the degree of compression of the spring by means ofthe adjuster screw-2 I, the flexible distortion of the membrane 24 may be more or less checked to suit prevail- 4 ing conditions.

Such a an adjustment being performed'when required, so as, to throttle the air flowpthe new position of hydrostatic-equilibrium of the. membrane ,willbring about a reductionof the airpressure in the compartment 28 with respect to. the gas-pressure in the compartment 30. This will lessen the rate of air flow through the nozzle-ll and-willconsequently cause an enrichment of the gaseous mixturewhile still automat- 'ically maintaining constant. the ratio of its gas and air constituentsirrespective of the feedrates inqthe intake pipes 15 and I5; Suchaction will make it possible to compensate for any loss which may happen inthe calorific value of the gas. due for example to fiuctuations in theoper- .ation of-the gas'producer ortqsimilar causes. A reverse adjustment may be readily effected if and when on the contrary the gas grows richer.

- The constructional modificationshown in' Fjig. 2 comprises. in thetube 3| of small sectional area which interconnects theprimary pipe-i5 and-the primary compartment 30 of the pressure-regulating chamber I 1 additional throttling means which may be constitutedv for example by a perforated or foran'linous diaphragm 32. The purpose ofthese throttling means is to prevent the membrane 24 fromoscillating or vibrating due to the repercussions caused-by the reciprocatory motion of the pistons in the cylinders of the engine (not shown) This. constructional modification further comprises a partition 33 firmly secured to the inner wall of the casing I! and formed with a. central hole 34 through which the push rod 21 is freely guided and with a port 35 which provides the necessary communi cation between the left hand side portion of the compartment '28 and its right "hand-side portion adjacentthe flexible membrane"24.

In the other constructional modification shown ;in Fig. 3, there is provided a second flexible membrane 36 also secured to the push rod 21 so as to move in unison with the first membrane 24.

The peripheral edge of this second membrane 36 is tightly clamped between a pair of flanges 31, 33 formed on the wall of the casing 11. One or more holes such as 39 are provided in the casing H to establish a free communication between the space 40 defined between the membranes 24 and 36 and the atmospheric air. The purpose-of this arrangement is principally to preclude the formation of a detonating gaseous mixture inside the pressure regulator 'if somehow thegas in the compartment 30 percolates through the membrane 24. Such a risk'is particularly to be feared where such gases as acetylene or hydrogen are used. In the modified arrangement shown in Fig. 3, shouldthe membrane 24 leak and the gas penetrate into the inter-membrane space 40, it readily escapes through the outlet hole or holes 39 and any cause of accident is thus inhibited.

The constructional modification shown in Fig. 4 comprises no mixing chamber such as the one shown at l2 in Figs. 1 to 3 inclusive. In this modification, the intermingling of the two con:- stituents of the gaseous mixture takes place in the various cylinders of the engine. Such cylinders are not shown in the drawing as they may be of any conventional form, as will be un.- derstood by anyone skilled in theart. In this construction, the intake pipe [5 extends to form a distribution manifold l5a which is divided into a number of branch pipes I'5b equal to the number of the engine cylinders. Each branch pipe advantageously has the Venturi outline as shown. The'flow of the gas through each branch pipe 151) is controlled by a'suitable valve such as a poppet valve 4| suitably operated with proper timing by any cammechanism by means common in the manufacture of internalcombustion engines The pipe 29 similarly extends to form a distribution manifold 29a which is provided with a number of branch pipes 291) equal to the number of the engine cylinders. Each branch pipe 29b advantageously has the Venturi outline shown. The flow of air through each branch pipe 291) is controlled by a' suitable valve'such as a poppet valve 42 suitably operated with proper timing by a cam mechanism as above stated: The actuations of-the valves 4| and 42 are of course so suitably timed and co-related as to permit proper intermingling of the two constituents of the gaseous mixture fed to the engine cylinders.

It will be seen that in this arrangement the detonating mixture forms itself inside each engine cylinder, whereby any danger of explosion outside the cylinder is prevented. I

Throughout the foregoing description, it has been assumed that theprimary intake pipe I5 is connected to the gas supply while thesecondary intake pipe I6 is connected to the air supply. This,- however, is not limitative and the reverse might be. the case, the air being then drawn in through the intake pipe l5, while the gas would be drawn in through the intake ing in communication with the secondary in- 1 pipe [6. The claims are correspondingly worded to include this alternative arrangement.

It will be seen that the aforesaid arrangement of parts permits the objects of the invention to be fulfilled inasmuch as, once the composition of the gaseous mixture has been manually adjusted to suit requirements, it is automatically maintained constant regardless of the operational speed and efiiciency of the engine, of the position occupied at any moment by thethrottle valve l4, and also of any loss of pressure which may happen in the gas feeding pipe up the pressure regulating device. This is due to the fact that in contradistinction to what exists in known feed devices the quantity of intake air admitted to the engine is not governed by the position of the throttle valve.

Numerous minor constructional details must be varied without departing from the scope of the subjoined claims which must be construed in a broad rather than in-a limitative sense.

, What is claimed is:

1. Device for feeding a gaseous mixture to an internal combustion engine, comprising a primary intake pipe for a constituent of the mixture. a secondary intake pipe for another constituent of the mixture, said secondary pipe being elbowed at its end, an enclosure into which the elbowed end of the secondary pipe projects, a flexible element tightly dividing said enclosure into sepa primary intake for a constituent of the mixture,

a secondary intake for another mixture constituent, an enclosure, a flexible membrane tightly dividing said enclosure into separate primary and secondary compartments, a tube of small section interconnecting the primary intake and'primary compartment, the end of the secondary intake projecting into the secondary compartment to provide communication.

therewith, a valve urged by spring means and controlling exclusively said communication, an adjuster for said spring means, a rigid interconnection between said membrane and valve, a mixing chamber communicating with the engine induction, and a pair of equivalently acting nozzles respectively connected with the primary intake and secondary compartment and both projecting beyond the wall of said mixing chamber into said mixing chamber.

3. Device for feeding a gaseous mixture to an internal combustion engine, comprising a primary intake for a constituent of the mixture, a secondary intake for another mixture constituent, an enclosure, a flexible membrane clamped along its periphery and tightly dividing said enclosure into separate primary and secondary compartments, a tube of small section interconnecting the primary intake and primary compartment, the secondary compartment beinto closing position, a hand-operated adjuster for said spring means, a rigid interconnection between said membrane and valve, a mixing chamber communicating with the engine induction manifold, and a pair of nozzles having Venturi outlines and identical thermodynamic characteristics respectively connected with both the primary intake and secondary compartment and projecting in converging relation into said mixing chamber.

4. Device for feeding a gaseous mixture to an internal combustion engine, comprising a primary intake for a constituent of the mixture, a secondary intake for another mixture constituent, an elongated enclosure, a flexible element clamped by its periphery and tightly dividing said enclosure into separate primary and secondary compartments, a throttled tube interconnecting the primary intake and primary compartment, the secondary compartment being in communication with the secondary intake, a valve controlling exclusively said latter communication, spring means urging said valve into closing position, an adjuster for said spring means, a rigid interconnection between said element and valve, a mixing chamber having oppositely slanting top faces and communicating with the engine induction, and a pair of thermodynamically equivalent throttled nozzles respectively connected with both the primary intake and secondary compartment and projecting in converging relation through said top faces of the mixing chamber.

5. Device for feeding an internal combustion engine with a gaseous mixture, comprising a primary intake for a constituent of the mixture, a secondary intake for another mixture constituent, an enclosure, a ported partition in said enclosure, a flexible pressure-responsive element clamped by its periphery in the enclosure and dividing it into separate primary and secondary compartments, a tube of small section interconnecting the primary intake and primary compartment, a throttling diaphragm in said tube, the secondary compartment being in communication with the secondary intake, a valve controlling exclusively said latter communication, spring means urging said valve into closing position, an adjuster for said spring means, a rigid interconnection between said flexible elements and valve, a mixing chamber communicating with the engine induction, and a pair of thermo-dynamically equivalent nozzles respectively connected with both the primary intake and secondary compartment and projecting into said mixing chamber at an angle to each other.

6. A feeding device as recited in claim 1 wherein a mixing chamber is arranged between the engine and said enclosure, the primary intake pipe terminating in a nozzle projecting angularly through the wall of said mixing chamber into the interior thereof, and a pipe connecting said secondary compartment with said mixing chamber, which pipe terminates in a nozzle projecting through the wall of said mixing chamber into the interior thereof at an angle converging toward said first-mentioned nozzle.

JEAN POINSIGNON. 

